Many multimedia devices employ touch screen technology. For example, a user may be able to interact with an image on a display screen by placing finger(s) or a pointing device (stylus) on a screen and enter a command by moving or tapping the finger/pointing device, to achieve the desired effect. The use of touch screen technology allows a user to easily navigate through menus and manipulate displayed data. Touch screen technology is also employed in various gaming applications.
The new touch screens also allow detection of the pointing device in vicinity of the screen plane without an actual physical touch. This allows a three-dimensional interaction with the device.
When touching the screen, the user may receive a feedback in way of a sound and/or visual signal or a physical (haptic) feedback.
Haptic technology is becoming more prevalent at least partially due to the evolution of touch screen devices. Haptic feedback is the use of forces, such as vibrations, to provide a user with the sensation of “feeling” changes on a touch screen or the like. The type of vibrations may be controlled, e.g., slow or fast vibrations, to simulate touching physical objects and elements on the screen. Thus, haptic feedback may provide a way of addressing the inability of a user to, for example, feel the visual keys of a keypad on a touch screen display.
Several haptic technologies are available now, including but not limited to vibration motor actuation, piezoelectric actuation, and electro-active polymer actuation.
When implementing haptic feedback, the force of the touch is not accounted for.